Certain aircraft and other large machines use modular assembly techniques. For example, the aircraft or machine may be assembled using relatively large functional groups. To illustrate, rather than assembling an entire aircraft from the ground up as a single unit, the assembly process may be broken up so that functional modules are assembled separately and later joined together. For example, wings may be assembled from many pieces at a first assembly location then attached as a single unit to a fuselage assembly at a second location. Placement of these modules or functional groups can be an important aspect of the assembly process. For example, when aircraft are being assembled, improper placement of a functional group may reduce operational efficiency of the aircraft.